Carburetor



F. ROTH CARBURETOR Oct. 24, 1933.

Filed Dec. 10, 1930 mvsmon fkw/wr For ATTORNEY Patented Get. 24,

CARBURETOR Frank Roth, New York, N. Y.

Application December 10, 1930 Serial No. 501,171

1 Claim.

The invention relates to an improved device for preparing charges for two-cycle internal combustion engines, and the object of the invention is to improve the charge,

that is, the mixture of liquid and air, to obtain greater power from the engine and to secure greater flexibility of operation. To the accomplishment of this end the invention consists in the improved apparatus hereinafter fully described out in the claim.

A preferred form of of the invention is illust ing drawing in which F and particularly pointed the improved apparatus rated in the accompanyig. l is a vertical section through a two-cycle engine of usual form with the improved charge-preparing device connected therewith; and Fig. 2 is an enlarged section of a portion of the charge-preparing device.

Referring more particularly to the drawing,

there is illustrated at 5,

in Fig. 1, the cylinder of a two-cycle internal combustion engine of usual construction and mode of operation.

a piston 6 for up and down To the piston 6 is attached cylinder 5 is mounted reciprocatory travel.

In the a connecting rod 7 associated with a crank 8 and shaft 9 located within a casing 10.

The cylinder 5 is provided with the usual intake is and outlet 15, the piston 6 being deflecting portion 16 bustible mixture to the inner or topv end of provided at one side with a to deflect the incoming comthe top of the combustion space 11 while the exhausted gases are passing out through the outlet The improved device for preparing the charge or 15. of the present invention combustion mixture comprises a carbureting chamber 18 formed in the section 19 of a which is provided with side of the cylinder 5 at other portion 21 of the pipean enlarged section 22 like structure one end of a flange 20 secured to the the intake port 14. The pipe 19 is provided with which constitutes the casing of a positive blower or supercharger of known design and operation for supplying a steady stream of air from the intake 24 to the carbureting chamber 18 by means of the impeller members 25 which rotate in the direction of the arrows placed upon them.

The means i or introducing the usual mixture of liquid hydrocarbon and air into the carbureting chamber 18 consists of a pipe 27 which enters the chamber at the intake side of a butterfly-type throttle valve 28 located within the pipe section 19 and mounted on one end of the pipe section 19.

naled in the walls of a rod 29 jour- The pipe 27 is provided with an inlet 30 for liquid hydrocarbon under pre ssure and also with an inlet 31 for compressed air located at a point between the liquid inlet 30 and the chamber 18. The air passing into the pipe 27 and thence into the carbureting chamber is' at a pressure slightly less than the pressure under which the liquid hydrocarbon is forced into the pipe 27 so as to J insure a steady iiow of the liquid hydrocarbon. The pressures at which both the liquid hydrocarbon and the compressed air enter the carbureting chamber is somewhat higher than the pressure at which the supplementary stream of air enters the carbureting chamber from the blower 25 to insure the proper introduction of the liquid and air mixture into the carbureting chamber. Since the carbureting chamber 18 is momentarily evacuated at the end of the power stroke of the piston 6 the back pressure built up in the chamber 18 under the action of the liquid and gas mixture entering the chamber from the inlets 3i) and 31 is negligible, and for practical purposes it may be regarded that there is a substantially steady stream of supplementary air entering the chamber from the impellers 25, inasmuch as the impellers provide a substantially air tight arrangement within the casing 22 which do not provide for any reverse flow or the air. The amount of liquid and air mixture admitted to the carbureting chamber 18 from the pipe 2? is controlled by a needle valve 38, which cooperates with a seat 34 formed in the inner end of the pipe 27 near the point where it joins with the pipe section 19. The stem section 35 of the needle valve 33 is journaled in the pipe 27 and its outer end is threaded, as at 36, to cooperate with an internally threaded enlargement 38 on the outer end of the pipe 2'7. The extremity of the valve stem 35 is provided with an arm 39 to which is pivoted one end of a link 41 the other end of which is pivoted to an arm 42 fixed on the outer end of the rod 29. An actuating member 43, adapted for manual or automatic operation, is pivotally connected with the free end of the arm 39 and the adjacent end of the link 41. The construction as a whole is so arranged that the throttle 28 and the needle valve 33 are opened and closed simultaneously. And it will be thus understood that proportionately to the opening and closing of the throttle 28 the needle valve 83 will be more or less opened or closed to admit a greater or less amou. t of liquid and air mixture to the carbureting chamber 18 according to therequirements of the service performed by the engine. It will be noted however, that irrespective of the amount of liquid and gas mixture admitted into the carbureting chamber 18 from take side of the throttle, said pipe having an inlet for liquid hydro-carbon and an inlet for air under pressure located between the liquid inlet and the chamber, a valve for controlling the amount of liquid and air mixture admitted to the chamber, pump means for forcing a supplementary steady stream of air under a pressure less than'that of the air entering through the air inlet, into the carbureting chamber, means for operating the valve, said throttle connected to the valve operating means and operated thereby for controlling said mixture outlet.

FRANK ROTH 

